Working chamber

ABSTRACT

A blasting unit has a working chamber with access for the introduction of a robot arm. In the region of the access, a sealing device is provided which is fastened to the robot arm or to the chamber wall. The working chamber serves for the blasting of workpieces by means of a blasting medium.

[0001] The present invention relates to a working chamber for a blasting unit which is provided with a robot arm for the manipulation of a workpiece to be blasted, with the working chamber having a chamber wall comprising an access for the introduction of the robot arm, and with a sealing device being provided in the region of the access and sealing between the robot arm and the chamber wall.

[0002] In such a working chamber, in particular workpieces of a complicated shape can be blasted, with the workpieces being brought into and taken out of the working chamber with the aid of the robot arm. Here, the sealing device must ensure that no blasting medium can exit the working chamber in the region of the access during blasting. It can be desirable in certain applications to move the robot arm, and thus the workpiece, during the blasting process. In this case, the sealing device must allow for a mobility of the robot arm about one or more axes.

[0003] It is the object of the present invention to improve a working chamber of the kind first named such that a sealing is possible between the robot arm and the working chamber which is cost favorable, i.e. less expensive in construction and apparatus.

[0004] This object is solved by the features of the independent claims and in particular in that the sealing device has a lock gate with at least one wing which is provided with an opening for the robot arm, with a sealing element being provided in the region of the opening which seals between the robot arm and the chamber wall.

[0005] In accordance with the invention, a lock gate is provided which is connected to the chamber wall, is cost favorable in manufacture and only has to be matched to the robot arms of different manufacturers in the region of its opening. The sealing device in accordance with the invention can be used universally and has no parts prone to disturbance which would have to be moved together with the robot arm. The chamber wall in particular does not have to be provided with a special leadthrough for the robot arm. The sealing takes place instantaneously on the closing of the lock gate.

[0006] Advantageous embodiments of the invention are described in the description, in the drawings and in the dependent claims.

[0007] In accordance with a first advantageous embodiment, the lock gate has at least one sliding or rotating wing. A fast opening of the lock gate is ensured in this manner in order to allow a fast change of workpiece.

[0008] In accordance with a further advantageous embodiment, the lock gate can have a plurality of wings which each have cut-outs which together form the opening. It is, for example, possible in this embodiment to provide the opening centrally in the lock gate, whereby the manipulation of the robot arm or its control is simplified.

[0009] A particularly simple solution in construction is provided in an embodiment in which a rim of the opening of the lock gate is provided with the sealing element. In this embodiment, the robot arm can be used without further components, sealing elements or control elements having to be fastened to it.

[0010] In accordance with a further advantageous embodiment, the sealing element is made substantially spherically and has a passage opening for the robot arm. In this embodiment, the sealing element can be pulled onto the robot arm, whereby a sealing engagement is provided between the robot arm and the chamber wall in the manner of a sealed ball bearing. Here, the sealing element can consist of elastic material or of wear-resistant, stiff material, with in this case a sealing lip or the like being able to be provided in the region of the gate lock.

[0011] In accordance with a further aspect of the invention, this relates to a working chamber for a blasting unit which is provided with a robot arm for the manipulation of a workpiece to be blasted, with the working chamber having a chamber wall comprising an access for the introduction of the robot arm, with an elastic sealing device being provided in the region of the access which seals between the robot arm and the chamber wall and which can be fastened to the robot arm.

[0012] To satisfy the object initially named, a latching means is here provided at the chamber wall which brings about a latching between the sealing device and the working chamber.

[0013] In this embodiment of the invention, a latching means, which latches between the sealing device fastened to the robot arm and the chamber wall, is not provided at the robot arm, but at the chamber wall such that the control members or control leads required for the actuation of the latching means do not have to be guided over the robot arm and be moved with it. Since the latching means are provided in a stationary manner in the region of the working chamber, a very simple construction results since the control of the latching means can likewise be guided in a stationary manner.

[0014] In accordance with an advantageous embodiment, the latching means can be actuable by a movement of the robot arm, in particular only by a movemement of the robot arm. Separate control and monitoring means can hereby be omitted, which further reduces the manufacturing and installation effort.

[0015] In accordance with a further embodiment of the invention, the latching means is designed in the manner of a bayonet fastening. Such a bayonet fastening can be manufactured cost favorably and can be opened or closed by a simple rotational movement of the robot arm.

[0016] In accordance with a further advantageous design of the invention, the sealing device has a self-supporting disk made of flexible material. Such an embodiment has the advantage that no supporting means or holding means have to be provided for the sealing device.

[0017] For the event that the sealing device does not consist of self-supporting material for the increase of the movability of the robot arm, in accordance with a further embodiment of the invention a supporting means, in particular a releasable supporting means, can be provided between an inner and an outer rim of the sealing device and can be moved together with the robot arm. Such a supporting means can support the sealing device for so long until it is latched to the chamber wall. Subsequently, the supporting means can be released from the sealing device, whereby a free movability of the robot arm results. The supporting means can then again be fastened to the sealing device for the removal of the robot arm from the working chamber.

[0018] The present invention will be described in the following purely by way of example with reference to advantageous embodiments and to the enclosed drawings. There are shown:

[0019]FIG. 1 and FIG. 2 a first embodiment of a working chamber;

[0020]FIG. 3 and FIG. 4 a second embodiment of a working chamber;

[0021]FIG. 5 and FIG. 6 a third embodiment of a working chamber;

[0022]FIG. 7 and FIG. 8 enlarged representations of the region VII of FIG. 5;

[0023]FIG. 9 and FIG. 10 a fourth embodiment of a working chamber; and

[0024]FIG. 11 an enlarged representation of a detail of FIG. 10.

[0025] Various embodiments of the invention will be described in the following with reference to the enclosed Figures, with the same reference numerals being used for the same components for a simplified representation.

[0026]FIGS. 1 and 2 show a first embodiment of a working chamber 12 for a blasting unit which is provided with a robot arm 10 for the manipulation of a workpiece (not shown) to be blasted. The working chamber 12, which is closed at all sides except for its front side, has a chamber wall 14 at its front side which has an access for the introduction of the robot arm 10. At the interior of the working chamber 12, a blasting device (not shown) is provided which propels the blasting medium in a blasting cone S onto a working region A inside the working chamber.

[0027] To allow the robot arm 10 with the workpiece located on it to be moved in and out of the working chamber and simultaneously to make possible a sealed movement of the robot arm 10 inside the working chamber 12, a lock gate is provided in this embodiment which has two sliding wings 20, 30 which can each be moved along the direction of the double arrows (FIG. 1) by an adjustment cylinder 22, 32. The two wings 20, 30 of the lock gate approximately form a square in a plan view in the closed state and each have a semi-circular cut-out 24A, 24B at the centre of their inwardly directed rim, with said cut-out producing a circular opening 24 for the passage of the robot arm 10 in the closed state of the wings 20, 30. The rim region of the opening of the lock gate is here provided with an elastic sealing element 26 which seals between the robot arm and the lock gate.

[0028] In the embodiment of a working chamber shown in FIGS. 1 and 2, the two wings 20 and 30 of the lock gate are opened with the aid of the adjustment cylinders 22, 32 prior to the start of the blasting process, which corresponds to the position shown by a chain-dotted line in FIG. 1. Subsequently, the front end of the robot arm 10 and the workpiece located thereon are moved into the interior of the working chamber 12 and brought into a central position such as is shown in FIG. 2. Subsequently, the two wings 20, 30 are closed such that the sealing element 26 sealingly contacts the outer periphery of the robot arm 10.

[0029] During the subsequent blasting process, the robot arm 10 can be moved to and fro in the direction of the double arrow in FIG. 2, i.e. along its longitudinal axis X in order to displace the workpiece within the blasting cone S. At the same time, the workpiece can be rotated about the central axis X of the robot arm along the shown double arrow to effect a uniform blasting. The rotation of the workpiece takes place here with the help of a rotational apparatus 11 which is arranged at the front end of the robot arm 10.

[0030] In the embodiment of a working chamber shown in FIGS. 3 and 4, the lock gate is formed by two swing wings 40, 60 which, in the closed state, form a ring with an inner circumference and an outer circumference, with the circular inner circumference defining an opening 44 through which the robot arm 10 can enter into the working chamber. The two swing wings 40 and 60 are each pivotable at their upper end about a horizontal pivot axis 41, 61 and are pivoted by one respective adjustment cylinder 42, 62. In the opened state, the two wings 40, 60 are located in the position shown by a chain-dotted line in FIG. 3 in which the robot arm 10, together with the workpiece located on it, can be moved along the central axis X through the opened access into the working chamber 12.

[0031] In this embodiment, a spherical sealing element 50 is provided as the sealing element between the robot arm and the lock gate, or the chamber wall 14, and has a central passage opening for the robot arm 10, i.e. the sealing element 50 is pulled onto the robot arm 10. The sealing element 50 can consist of rubber or plastic and allows a pivoting of the robot arm 10 inside the working chamber 12 in the manner of a ball joint, with a complete sealing of the working chamber always being ensured. The workpiece located at the front end of the robot arm 10 can hereby not only be rotated about the axis X with the help of the rotational drive 11, but a movement about the center of the sealing element 50 along the shown double arrow is also possible in order to move the workpiece inside the blasting cone S.

[0032] FIGS. 5 to 8 show a third embodiment of the invention in which an elastic sealing device, which can be fastened to the robot arm, is provided between the robot arm and the chamber wall in the region of the access in the chamber wall 14

[0033] In this third embodiment, an elastic rubber disk 70 is arranged at the robot arm 10 and is self-supporting. The rubber disk 70 has a circular circumference and is sealingly pulled onto the robot arm 10 which moves together with the rubber disk 70.

[0034] A ring receiver 72 which corresponds to the outer circumference of the rubber disk 70 is provided in the chamber wall 14 and the rubber disk 70 can be matchingly inserted into this. A plurality of latching means, four in the embodiment shown, are distributed over the outer periphery of the ring receiver 72 in order to latch the rubber disk 70 in the ring receiver 72 at the chamber wall 14. For this purpose, pins 74 are provided at the rubber disk 70 which project radially beyond the outer circumference of the rubber disk 70 and which cooperate with mounting slots 76 (FIG. 8) which are provided at the ring receiver 72. As FIG. 8 shows, the mounting slots 76 are designed in the manner of a bayonet fastening such that the rubber disk 70 can be latched at the ring receiver 72 by insertion of the pins 74 into the mounting slots 76 and by rotation of the rubber disk 70 counter clockwise (FIG. 1). The latching movement can here be carried out solely by a corresponding movement of the robot arm 10, i.e. the rubber disk 70 is brought into contact with the chamber wall 14 by its pins 74 such that the pins 74 engage into the mounting slots 76 and are latched in these. In addition, a spring-loaded locking bolt or the like can be provided in order to prevent an accidental release of the pin 74 from the mounting slots 76.

[0035] Since the rubber disk 70 is flexible overall, the robot arm 10 moved into the chamber can also be tilted when the rubber disk 70 is latched at the chamber wall 14.

[0036] For the removal of the workpiece from the working chamber 12, the robot arm 10 is pivoted somewhat clockwise about the axis X (in FIG. 6) until the spring-loaded locking bolt (not shown) is overcome and the pins 74 come free of the mounting slots 76. The robot arm 10 can subsequently be retracted, whereby the rubber disk 70 releases from the chamber wall 14 (cf. broken line representation in FIG. 6).

[0037] FIGS. 9 to 11 show a fourth embodiment of a working chamber in which the sealing device is fastened to the robot arm 10 between the robot arm 10 and the working chamber 12.

[0038] In this embodiment, a circular bellows 80 is provided as the sealing device and is fastened to the outer periphery of the robot arm 10. The bellows 80 is highly flexible and therefore not self-supporting. To provide sufficient support prior to the latching of the bellows 80 to the chamber wall 14, releasable supporting means are provided between the inner periphery and the outer periphery of the bellows in the form of three support levers 82 distributed evenly over the periphery which can be pivoted by means of adjustment cylinders 84 about pivot axes 86 which extend tangentially to the outer periphery of the robot arm 10.

[0039] As FIG. 11 shows, the support levers 82 can be pivoted from the retracted position shown by broken lines into a position pivoted forward at which the outer periphery of the bellows 80 is set between the ends of the support lever 82. A spring-loaded, self-actuating clamp 88 is located at the ends of each supporting element 82 and cooperates with a ball spigot 89 provided at the outer periphery of the bellows 80.

[0040] The circular opening provided in the chamber wall 14 as an access for the robot arm 10 is bounded by a ring receiver 100 into which the outer periphery of the bellows can be matchingly set. A plurality, four in the embodiment shown, of pneumatically actuable latching elements 102 (cf. FIG. 9) are provided distributed over the outer periphery of the ring receiver mount 100 in the form of pneumatically actuable locking pins with which the bellows 80 can be latched to the chamber wall 14.

[0041] In the above-described fourth embodiment, a workpiece fastened to the front end of the robot arm 10 is moved into the working chamber 12, with the bellows 80 being located in the position shown in FIG. 10. In this position, the clamps 88 are latched with the ball spigots 89 and the support levers 82 are located in the moved out position such that the bellows 80 is set between the support levers 82 and can be set against the ring receiver 100 together with the robot arm 10. When the bellows 80 is in the position shown in the Figures, the latch elements 102 are activated, whereby the bellows 80 is fixed at their outer periphery to the chamber wall 14. Hereupon, the adjustment cylinders 84 are actuated such that the clamps 88 come free from the ball spigots 89 (cf. chain dotted representation in FIG. 10). Hereupon, the robot arm 10 can be moved both in the direction of the axis 10 and about the axis Y and can be pivoted as desired about a vertical pivot axis. At the same time, a rotation about the axis X is possible with the help of the rotational device 11.

REFERENCE NUMERAL LIST

[0042]10 robot arm

[0043]11 rotational apparatus

[0044]12 working chamber

[0045]14 chamber wall

[0046]20 sliding wing

[0047]22 adjustment cylinder

[0048]24 opening

[0049]24A, 24B cut-out

[0050]26 sealing element

[0051]30 sliding wing

[0052]32 adjustment cylinder

[0053]40 swing wing

[0054]41 pivot axis

[0055]42 adjustment cylinder

[0056]44 opening

[0057]50 sealing element

[0058]60 swing wing

[0059]61 pivot axis

[0060]62 adjustment cylinder

[0061]70 rubber disk

[0062]72 ring receiver

[0063]74 pin

[0064]76 mounting slot

[0065]80 bellows

[0066]82 support lever

[0067]84 adjustment cylinder

[0068]86 pivot axis

[0069]88 clamp

[0070]89 ball spigot

[0071]100 ring receiver

[0072]102 latching element

[0073] A working region

[0074] S blast cone

[0075] X, Y axes 

1. A working chamber for a blasting unit which is provided with a robot arm (10) for the manipulation of a workpiece to be blasted, comprising a chamber wall (14) which has an access for the introduction of the robot arm (10), with a sealing device being provided in the region of the access which seals between the robot arm and the chamber wall (14), wherein the sealing device has a lock gate (20, 30; 40, 60) with at least one wing and provided with an opening (24, 44) for the robot arm (10), with a sealing element (26, 50) being provided in the region of the opening (24, 44) which seals between the robot arm (10) and the chamber wall (14).
 2. A working chamber in accordance with claim 1, wherein the lock gate has at least one sliding wing (20, 30) or swing wing (40, 60).
 3. A working chamber in accordance with claim 1, wherein the lock gate has a plurality of wings (20, 30; 40, 60) which each have cutouts (24A, 24B; 44) which jointly form the opening.
 4. A working chamber in accordance with claim 1, wherein a rim of the opening (24) of the lock gate is provided with the sealing element (26).
 5. A working chamber in accordance with claim 1, wherein the sealing element comprises a substantially spherical element (50) which is provided with a passage opening for the robot arm (10).
 6. A working chamber for a blasting unit which is provided with a robot arm (10) for the manipulation of a workpiece to be blasted, comprising a chamber wall (14) which has an access for the introduction of the robot arm (10), with an elastic sealing device (70, 80) being provided in the region of the access which seals between the robot arm (10) and the chamber wall (14), with the sealing device (70, 80) being able to be fastened to the robot arm (10), wherein a latching means (72, 76; 102) is provided at the chamber wall (14) which effects a latching between the sealing device (70, 80) and the working chamber (12).
 7. A working chamber in accordance with claim 6, wherein the latching means (102) is actuable by a movement of the robot arm (10).
 8. A working chamber in accordance with claim 7, wherein the latching means (76) is made in the manner of a bayonet fastener.
 9. A working chamber in accordance with claim 7, wherein the sealing device has a self-supporting disk (70) made of flexible material.
 10. A working chamber in accordance with claim 7, wherein a supporting means (82, 88), in particular a releasable supporting means, is provided between an inner and an outer rim of the sealing device (10) and is movable together with the robot arm (10).
 11. A working chamber in accordance with claim 10, wherein the supporting means includes at least one pivoted lever (82).
 12. A working chamber in accordance with claim 7, characterized in that the sealing device is designed in the manner of a bellows (80). 